O'Dean households in each
county in the Primary Valuation property survey of 1847-64.

numerous: Belfast, Dublin, Cork and all areas. It corresponds to a number of names: Norman le Den, one of the "Tribes of Galway"; Ó Déaghain in Tipperary; Mac an Déaghain in Donegal. The latter derive from déaghan, dean (ecclesiastical).MIF.